People in Ferguson, Mo., didn't wait for news conferences, petitions or legal action to bring national attention to their streets after a police officer fatally shot an unarmed black teen.

They snapped a photo. They used a hashtag. And, in the span of five days, their growing, stinging social media cloud of real-time updates shaped a raw public discourse about the teen, Michael Brown, race relations and police force in the USA.

Rod Winzer, 18, from Garland, Texas posted these two images to his Twitter account as part of the campaign #IfTheyGunnedMeDown.(Photo: Courtesy of @TopFlightRod via Twitter)

What's happening in Ferguson is "eerily familiar" to protests in Egypt, Turkey and Ukraine, said Zeynep Tufekci, assistant professor at the University of North Carolina, who teaches about the social impacts of technology.

"You see a livestream by a couple of scrappy citizens, regular media getting arrested, over-policing ... then national media and international media waking up to it," Tufekci said. "It's just unfolded the same way."

A particular kind of story resonates on social media, one that aligns with the events unfolding in Ferguson, said Scott Talan, assistant professor at American University's School of Communication.

Ferguson taps into strong emotions and the familiarity of this narrative.

"When something people view generally as wrong, bad, immoral or unethical happens again and again, people won't say, 'We've seen it before.' At least on social media, people will say, 'Why is this happening again?" Talan said, citing the #Neveragain hashtag in response to school shootings.

But social media have changed not only what gets noticed, but also who gets noticed. In this case, it's the residents of Ferguson who are taking the spotlight.

"Usually in an activist campaign like this, there would be a trusted leader speaking out for the cause. We don't see that with Ferguson, and that's a positive in this case. We see a community standing up for itself," Karpf said.

A local official, St. Louis Alderman Antonio French, had been documenting the protests and police reaction through Vine, a micro-video social media site, and tweeting his vines out with the hashtag #Ferguson. He was arrested Wednesday and spent the night in jail.

"After a night in the #Ferguson jail, I'm free. My staffers who were also arrested last night are also free. Thank you for all the support," French tweeted Thursday. It has been re-tweeted more than 4,000 times.

Social media can be an effective form of activism, but experts also express concern over the validity of information disseminated so quickly and freely.

On Thursday, hacker activist group Anonymous released a name supposedly of the officer who shot Brown, but it turned out to be wrong. It was someone who is not on the Ferguson police force. A relative at his home expressed fear over what someone getting the false information might do.

Twitter suspended the Anonymous account.

"The nature and speed of the Internet can cause people to jump to conclusions and rush ahead, but it's also self-correcting," Talan said.

When protests in Ferguson began, Tufekci recalls online conversations questioning whether the situation would make the news.